As per Spaceweather.com:GEOMAGNETIC STORM UPDATE: A CME (coronal mass ejection) propelled toward Earth by this morning's X5-class solar flare is expected to reach our planet on March 8th at 0625 UT (+/- 7 hr). Analysts at the Goddard Space Weather Lab, who prepared the CME's forecast track, say the impact could spark a strong-to-severe geomagnetic storm. Sky watchers at all latitudes should be alert for auroras.And if you're wondering what exactly this "X-class solar flare" is... well basically it's a giant explosion on the sun that sends energy, light and high speed particles far into space. It's one of the most violent and energetic events in our solar system, and can have strong effects on earth if it's directed our way. Have a look here for more info.